Potassium phosphates, offering to the plants important elements P/K in a soluble form, belong among the most popular fertilizers, but some of them are difficult to store and manipulate. For example, rather basic dipotassium phosphate (DKP) would make a quite desirable combination with rather acidic monopotassium phosphate (MPK), but the inherent instability of the former in regard to water content, due to its hygroscopicity, makes any manipulations difficult. Ideally, fertilizers should be easily manufactured and should have suitable consistency for easy handling. The art still does not provide enough fertilizers with the required characteristics, suitable for all situations. WO2009/072106 provides a process for manufacturing a solid, freely flowing particulate fertilizer of the formula K3H3(PO4)2 from MPK and potassium hydroxide (KOH). It is an object of the present invention to provide a method for manufacturing an easy-to-handle granular P/K fertilizer from commodity chemicals.
It is further an object of the invention to provide a solid fertilizer supplying phosphorus and potassium, essentially consisting of K2O and P2O5 in the weight ratio 1:1, which is freely-flowing and without tendency to cake.
It is another object of this invention to provide a method for manufacturing a particulate, easy-to-handle P/K fertilizer from phosphoric acid and potassium hydroxide.
Other objects and advantages of present invention will appear as description proceeds.